Nail Polish Remover
The first thing you need to do is read the label on your garment. Do NOT use this household remedy if the garment is made of modacrylic, acetate or triacetate, because the remover can actually dissolve the fabric.
For washable fabrics, place a white towel directly under the stain. For example, if you have a shirt, put the towel inside of the shirt so it does not go through to the back side of the garment.
Dip a cotton swab or white cloth in the nail polish remover and work from the outside of the stain in so it does not spread further. Keep dabbing gently and you should see the polish transferring to the swab or the towel.
Crazy as it sounds Bug Sprays such as OFF can help remove nail polish from clothing.
Place a white towel directly under the stain so it does not bleed through other side of garment and liberally spray the bug spray until the stain is saturated. Leave spray on for about ten minutes then use an old toothbrush or nail brush to brush the stain out, I recommend you learn about Cladding Respraying.
Again however, be careful of the material of the garment.
Motsenbocker’s Lift Off #3
Normally found in the paint section of stores such as Home Depot – this is a great item to always have around the house. It works great for removing nail polish stains (it is even listed as one of the uses on the bottle) as well as other accidental stains such as ink stains, permanent marker stains, graffiti removal and more!
Spray ‘N Wash
Spray “n Wash can also help remove some nail polish stains, but not all. It seems to work better on lighter colored polishes. If you have some in the house however, try spraying it on garment and rubbing with a soft old toothbrush or nail brush.
Dry Clean Only Items
Chances are you might not want to mess around with these types of garments. Bring it to your local dry cleaner and be sure to point out the stain to them. They would probably have more success getting it out than you would.